xref: /openbmc/u-boot/lib/hexdump.c (revision c882163b09b8a2c52e3dd8acd7d296d6d06d1f2e)
1  // SPDX-License-Identifier: GPL-2.0+
2  /*
3   * lib/hexdump.c
4   *
5   * This program is free software; you can redistribute it and/or modify
6   * it under the terms of the GNU General Public License version 2 as
7   * published by the Free Software Foundation. See README and COPYING for
8   * more details.
9   */
10  
11  #include <common.h>
12  #include <hexdump.h>
13  #include <linux/ctype.h>
14  #include <linux/compat.h>
15  #include <linux/log2.h>
16  #include <asm/unaligned.h>
17  
18  const char hex_asc[] = "0123456789abcdef";
19  const char hex_asc_upper[] = "0123456789ABCDEF";
20  
21  #ifdef CONFIG_HEXDUMP
22  /**
23   * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory
24   * @buf: data blob to dump
25   * @len: number of bytes in the @buf
26   * @rowsize: number of bytes to print per line; must be 16 or 32
27   * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
28   * @linebuf: where to put the converted data
29   * @linebuflen: total size of @linebuf, including space for terminating NUL
30   * @ascii: include ASCII after the hex output
31   *
32   * hex_dump_to_buffer() works on one "line" of output at a time, i.e.,
33   * 16 or 32 bytes of input data converted to hex + ASCII output.
34   *
35   * Given a buffer of u8 data, hex_dump_to_buffer() converts the input data
36   * to a hex + ASCII dump at the supplied memory location.
37   * The converted output is always NUL-terminated.
38   *
39   * E.g.:
40   *   hex_dump_to_buffer(frame->data, frame->len, 16, 1,
41   *			linebuf, sizeof(linebuf), true);
42   *
43   * example output buffer:
44   * 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f  @ABCDEFGHIJKLMNO
45   *
46   * Return:
47   * The amount of bytes placed in the buffer without terminating NUL. If the
48   * output was truncated, then the return value is the number of bytes
49   * (excluding the terminating NUL) which would have been written to the final
50   * string if enough space had been available.
51   */
52  int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, int groupsize,
53  		       char *linebuf, size_t linebuflen, bool ascii)
54  {
55  	const u8 *ptr = buf;
56  	int ngroups;
57  	u8 ch;
58  	int j, lx = 0;
59  	int ascii_column;
60  	int ret;
61  
62  	if (rowsize != 16 && rowsize != 32)
63  		rowsize = 16;
64  
65  	if (len > rowsize)		/* limit to one line at a time */
66  		len = rowsize;
67  	if (!is_power_of_2(groupsize) || groupsize > 8)
68  		groupsize = 1;
69  	if ((len % groupsize) != 0)	/* no mixed size output */
70  		groupsize = 1;
71  
72  	ngroups = len / groupsize;
73  	ascii_column = rowsize * 2 + rowsize / groupsize + 1;
74  
75  	if (!linebuflen)
76  		goto overflow1;
77  
78  	if (!len)
79  		goto nil;
80  
81  	if (groupsize == 8) {
82  		const u64 *ptr8 = buf;
83  
84  		for (j = 0; j < ngroups; j++) {
85  			ret = snprintf(linebuf + lx, linebuflen - lx,
86  				       "%s%16.16llx", j ? " " : "",
87  				       get_unaligned(ptr8 + j));
88  			if (ret >= linebuflen - lx)
89  				goto overflow1;
90  			lx += ret;
91  		}
92  	} else if (groupsize == 4) {
93  		const u32 *ptr4 = buf;
94  
95  		for (j = 0; j < ngroups; j++) {
96  			ret = snprintf(linebuf + lx, linebuflen - lx,
97  				       "%s%8.8x", j ? " " : "",
98  				       get_unaligned(ptr4 + j));
99  			if (ret >= linebuflen - lx)
100  				goto overflow1;
101  			lx += ret;
102  		}
103  	} else if (groupsize == 2) {
104  		const u16 *ptr2 = buf;
105  
106  		for (j = 0; j < ngroups; j++) {
107  			ret = snprintf(linebuf + lx, linebuflen - lx,
108  				       "%s%4.4x", j ? " " : "",
109  				       get_unaligned(ptr2 + j));
110  			if (ret >= linebuflen - lx)
111  				goto overflow1;
112  			lx += ret;
113  		}
114  	} else {
115  		for (j = 0; j < len; j++) {
116  			if (linebuflen < lx + 2)
117  				goto overflow2;
118  			ch = ptr[j];
119  			linebuf[lx++] = hex_asc_hi(ch);
120  			if (linebuflen < lx + 2)
121  				goto overflow2;
122  			linebuf[lx++] = hex_asc_lo(ch);
123  			if (linebuflen < lx + 2)
124  				goto overflow2;
125  			linebuf[lx++] = ' ';
126  		}
127  		if (j)
128  			lx--;
129  	}
130  	if (!ascii)
131  		goto nil;
132  
133  	while (lx < ascii_column) {
134  		if (linebuflen < lx + 2)
135  			goto overflow2;
136  		linebuf[lx++] = ' ';
137  	}
138  	for (j = 0; j < len; j++) {
139  		if (linebuflen < lx + 2)
140  			goto overflow2;
141  		ch = ptr[j];
142  		linebuf[lx++] = (isascii(ch) && isprint(ch)) ? ch : '.';
143  	}
144  nil:
145  	linebuf[lx] = '\0';
146  	return lx;
147  overflow2:
148  	linebuf[lx++] = '\0';
149  overflow1:
150  	return ascii ? ascii_column + len : (groupsize * 2 + 1) * ngroups - 1;
151  }
152  
153  /**
154   * print_hex_dump - print a text hex dump to syslog for a binary blob of data
155   * @prefix_str: string to prefix each line with;
156   *  caller supplies trailing spaces for alignment if desired
157   * @prefix_type: controls whether prefix of an offset, address, or none
158   *  is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
159   * @rowsize: number of bytes to print per line; must be 16 or 32
160   * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
161   * @buf: data blob to dump
162   * @len: number of bytes in the @buf
163   * @ascii: include ASCII after the hex output
164   *
165   * Given a buffer of u8 data, print_hex_dump() prints a hex + ASCII dump
166   * to the stdio, with an optional leading prefix.
167   *
168   * print_hex_dump() works on one "line" of output at a time, i.e.,
169   * 16 or 32 bytes of input data converted to hex + ASCII output.
170   * print_hex_dump() iterates over the entire input @buf, breaking it into
171   * "line size" chunks to format and print.
172   *
173   * E.g.:
174   *   print_hex_dump("raw data: ", DUMP_PREFIX_ADDRESS, 16, 1, frame->data,
175   *                  frame->len, true);
176   *
177   * Example output using %DUMP_PREFIX_OFFSET and 1-byte mode:
178   * 0009ab42: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f  @ABCDEFGHIJKLMNO
179   * Example output using %DUMP_PREFIX_ADDRESS and 4-byte mode:
180   * ffffffff88089af0: 73727170 77767574 7b7a7978 7f7e7d7c  pqrstuvwxyz{|}~.
181   */
182  void print_hex_dump(const char *prefix_str, int prefix_type, int rowsize,
183  		    int groupsize, const void *buf, size_t len, bool ascii)
184  {
185  	const u8 *ptr = buf;
186  	int i, linelen, remaining = len;
187  	char linebuf[32 * 3 + 2 + 32 + 1];
188  
189  	if (rowsize != 16 && rowsize != 32)
190  		rowsize = 16;
191  
192  	for (i = 0; i < len; i += rowsize) {
193  		linelen = min(remaining, rowsize);
194  		remaining -= rowsize;
195  
196  		hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
197  				   linebuf, sizeof(linebuf), ascii);
198  
199  		switch (prefix_type) {
200  		case DUMP_PREFIX_ADDRESS:
201  			printf("%s%p: %s\n", prefix_str, ptr + i, linebuf);
202  			break;
203  		case DUMP_PREFIX_OFFSET:
204  			printf("%s%.8x: %s\n", prefix_str, i, linebuf);
205  			break;
206  		default:
207  			printf("%s%s\n", prefix_str, linebuf);
208  			break;
209  		}
210  	}
211  }
212  
213  /**
214   * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
215   * @prefix_str: string to prefix each line with;
216   *  caller supplies trailing spaces for alignment if desired
217   * @prefix_type: controls whether prefix of an offset, address, or none
218   *  is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
219   * @buf: data blob to dump
220   * @len: number of bytes in the @buf
221   *
222   * Calls print_hex_dump(), rowsize of 16, groupsize of 1,
223   * and ASCII output included.
224   */
225  void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
226  			  const void *buf, size_t len)
227  {
228  	print_hex_dump(prefix_str, prefix_type, 16, 1, buf, len, true);
229  }
230  #else
231  /*
232   * Some code in U-Boot copy-pasted from Linux kernel uses both
233   * functions below so to keep stuff compilable we keep these stubs here.
234   */
235  void print_hex_dump(const char *prefix_str, int prefix_type,
236  				  int rowsize, int groupsize, const void *buf,
237  				  size_t len, bool ascii)
238  {
239  }
240  
241  void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
242  					const void *buf, size_t len)
243  {
244  }
245  #endif /* CONFIG_HEXDUMP */
246